In these types of the conventional IC card and the card readers accessible using a non-contact method, generally, an antenna coil is embedded in the IC card, and, in the card reader, an antenna coil is arranged so as to come close to the antenna coil within the IC card inserted into a card insertion slot.
With these conventional IC card and card reader, when the IC card is inserted in the card insertion slot of the card reader, the card reader detects insertion of the IC card, modulates a carrier signal with an access signal to generate a high-frequency signal, and then transmits the high-frequency signal to the IC card from the antenna coil.
On the other hand, the IC card receives with the embedded antenna coil the high-frequency signal transmitted from the antenna coil of the card reader, and then rectifies the received high-frequency signal to generate the access signal and direct-current voltage.
Subsequently, the IC card activates the direct voltage as operating power, and transmits answer back data for the access signal to the card reader. Mutual communications are thus performed between the card reader and the IC card.